Citrate ester compositions which are useful as compatible components in a resinous system for sheet molding compositions and have a general formula ##STR1## wherein X is selected from the group consisting of --OC.sub.3 H.sub.6).sub.3 --OCH.sub.3 and OH are disclosed. Also disclosed is a sheet molding composition which includes a four component resinous system comprising (a) an unsaturated polyester comprising a polycondensation product of one or more dihydric alcohols and one or more ethylenically unsaturated polycarboxylic acids; (b) one or more low-profile thermoplastic polymer additives which cause phase separation and internal voids during the curing reaction; (c) one or more olefinically unsaturated monomers which copolymerize with the unsaturated polyester; and, (d) one or more compatible components which remain compatible when the polyester and monomer cure and impart improved surface characteristics when added to typical low-profile resin systems.